Replacing/upgrading a Mini (or other internal) SD card with Linux

[bobobo1618]

You'll need either a full Linux installation or a live USB with at least 4GB of free space. Google "pendrivelinux" and the first result should be an entire site dedicated to telling you how to make a live USB. I recommend Ubuntu, it's easy for new people to use.

So, steps:

1. Open a terminal (if you're on Ubuntu, type terminal in the search box)
2. Plug in the internal SD card from the Kobo Mini
3. Type "sudo fdisk -l" (That's a lower case L for people with silly fonts)
4. You should see a ton of stuff, most importantly, each section should have a header like "Disk /dev/sda: 64.0 GB, 64023257088 bytes, 125045424 sectors". Look for one with "Disk /dev/sd[probably the highest letter]: [Size of your SD card]..." and note the letter, it's important.
5. If you're on a full blown installation, you're about to create a 4GB image of the card, so cd to somewhere useful. If you're on a LiveUSB, look through the results of "fdisk -l" for the /dev/sd[letter][number] that corresponds to a data partition on your hard drive (should be quite large and have a ton of blocks) and type "sudo mount /dev/sd[letter][number] (for example, /dev/sda1) /mnt" then type "cd /mnt".
6. Type "sudo dd if=/dev/sd[letter corresponding to your SD card] of=kobosd.img bs=4M" then wait a bit. It won't show any progress but it's copying 4GB of data from your card.
7. Eject the card from the kobo and insert the new card (of whatever size) and type "fdisk -l" again. Look for the letter again. It will possibly be the same letter that the Kobo SD had.
8. Type "sudo dd if=kobosd.img of=/dev/sd[new letter] bs=4M" and wait again. It'll probably be slower than last time since you're going to the card instead of from.
9. Type "sudo fdisk /dev/sd[new letter of SD"
10. Press "p" and the partitions should be printed. Make a note of the start value of the last partition and copy it or write it down somewhere. Also the number after "/dev/sd[letter", that's important too.
11. Type "d" and when prompted, enter the number you just chose.
12. Type "n" and when prompted for type, just hit enter. Then enter that number again. When it asks for a starting position, enter the start value from before. When it prompts for an end value, just hit enter, this should use the maximum available space.
13. Press "t", "3" then "b" and hit enter.
14. Type "w" then "q"

You're done! You can put the SD back in the Kobo Mini.

I've only tested this with my Mini and a 16GB Class 10 Patriot MicroSDHC card.

If you screw up during the whole fdisk thing, just hit q and start again. Nothing is modified on the disk until you press w.

To get the SD out of (and into) the Mini, all you need to do is pull off the back cover and unscrew the plastic cover behind that. The SD slot is rather obvious and easy to use.

EDIT: The resize method I listed above may have issues with the Kobo picking up the size of the new FS. Ignore the 'sudo fdisk' line and everything below it. Instead run 'sudo gparted' from the console (should be preinstalled on Ubuntu), then select '/dev/sdX' in the top right where 'sdX' is the same one you've been using the whole time. Then right click the bottom item (the label should be 'KOBOeReader' in the list that shows there and click 'resize/move', set 'free space (both before and after) to 0 then click 'resize/move'. Then just click Edit->Apply all operations. It'll give you a warning but that's fine. It's a much easier and technically superior way of doing things.

If you have done the instructions I already put there and find your Kobo isn't detecting the free space, you can put the SD back in, type 'sudo gparted', click the top right thing and select your card (the size should make it recognizable) then right click 'check' then Edit->Apply All Operations. The Kobo should pick it up after that.

[jusmee]

heh... at first reading of your title, it sounded like you were putting a linux installation on the Kobo! I see you are just using linux as the system that transfers the SD card image to a new card.

So, a few questions. Do all Kobo devices use a removable SD card? Are there any downloadable images of the different Kobo SD cards in case of stuff-ups? Are there instructions for the different Kobo models on how to open the case without damaging it (mine is a KT) ?

[GeoffR]

Do you need to format the new partition? Or will the device do that itself when it finds the partition is unformatted?

[GeoffR]

Also, do you think there would be any noticable benefit from using a class 10 micro SD card? I saw in this thread that the Glo comes standard with a class 4 card: https://www.mobileread.com/forums/sho...d.php?t=200669

[murg]

Originally Posted by jusmee

Do all Kobo devices use a removable SD card? Are there any downloadable images of the different Kobo SD cards in case of stuff-ups? Are there instructions for the different Kobo models on how to open the case without damaging it (mine is a KT) ?

Some of the Touches have a non-removable flash memory chip, rather than the SD card.

[jusmee]

Originally Posted by murg

Some of the Touches have a non-removable flash memory chip, rather than the SD card.

Thanks. I'll probably need to open mine to find out. What's the best way to do that, avoiding damage? Does the back just pop off?

[bobobo1618]

Originally Posted by jusmee

Thanks. I'll probably need to open mine to find out. What's the best way to do that, avoiding damage? Does the back just pop off?

For my Mini, you just pull off the back cover (takes a bit of force but be careful) then unscrew the 6 screws behind that. Same deal with the second layer.

Originally Posted by GeoffR

Also, do you think there would be any noticable benefit from using a class 10 micro SD card? I saw in this thread that the Glo comes standard with a class 4 card: https://www.mobileread.com/forums/sho...d.php?t=200669

Benefits from Class 10? Not really. I just happened to have one laying around (I'm like that). It'll make imaging go faster though.
And yeah, the Mini I bought came with a standard Sandisk 4GB Class 4 SDHC.

Originally Posted by GeoffR

Do you need to format the new partition? Or will the device do that itself when it finds the partition is unformatted?

The whole point of this method is that the partition remains formatted. This means that all your existing books and such remain intact It's complicated but the short of it is that we're only modifying the partition table, not the actual data on the partition.

Originally Posted by jusmee

heh... at first reading of your title, it sounded like you were putting a linux installation on the Kobo! I see you are just using linux as the system that transfers the SD card image to a new card.

So, a few questions. Do all Kobo devices use a removable SD card? Are there any downloadable images of the different Kobo SD cards in case of stuff-ups? Are there instructions for the different Kobo models on how to open the case without damaging it (mine is a KT) ?

Well the Kobo does actually run Linux :P I had a poke around the card. If you're a Linux person yourself, the first partition is simple EXT3 which you can mount through Nautilus or whatever. As for running third party software, I think that should actually be doable. The device uses a standard ARM Cortex A8 when you get down to it. As for useful software, I'm not too sure. SSH should probably run but you'd need to get a shell on there too. You definitely won't get Ubuntu or something running though.

As for the rest:
Removable SD card: Not sure. Look for the teardowns or open it up yourself.
Downloadable images: Nope. I recommend you simply keep the kobosd.img. Nothing before the stage where it's created can harm the device and that image can be used to restore it to what it was before you played with it. If someone wants to upload one, sure. I also noticed that the card had a second recovery partition. I imagine that can be used to factory reset if you're playing with the system itself.
How to open it: Once again, look for the teardowns. I found how to open the mini and create this guide using this: https://www.mobileread.com/forums/sho...d.php?t=193321

Also, apparently I can't edit the first post of the thread...? Why? I just wanted to say what exactly it was that this does XD

Another edit: according to this, the back of the KT works just the same as the Mini.

[Ladyrixx]

I did mine on Saturday. It now has a nice 16GB card. (^_^) I got to put all the books back on that I had to cut when I went from the EZ Reader to Kobo mini. It even remembered the position that I was in on the book I was reading.

Thanks so much!

[bobobo1618]

Originally Posted by Ladyrixx

I did mine on Saturday. It now has a nice 16GB card. (^_^) I got to put all the books back on that I had to cut when I went from the EZ Reader to Kobo mini. It even remembered the position that I was in on the book I was reading.

Thanks so much!

You are most welcome ma'am!

Like your picture :P

And honestly, I'm glad my instructions were actually clear enough to be useful... This is the first proper tutorial I've done.

[davidfor]

Has anyone who has replaced the internal SD card with a larger one done a factory reset? If so, what happened?

[GeoffR]

Could I ask those of you who upgrade your internal SD card, what type of card you used (brand/size/class) and whether it had any effect on the speed or stability of the reader?

I gather from some other sites that class 2 or 4 cards are often best for hosting the operating system (i.e. Kobo's internal card), while class 6 or class 10 cards are better for large data files (Kobo's external card perhaps?)

I also heard that not all types of card work well with Kobo readers, so it might be useful for those of us contemplating an upgrade to know which cards to avoid.

[bobobo1618]

Originally Posted by davidfor

Has anyone who has replaced the internal SD card with a larger one done a factory reset? If so, what happened?

This is pure speculation but going off the presence of the recovery partition, I'm guessing it'll copy that to the system partition and do a quick format of the main data partition (but hopefully leave the partition table (resized partition) intact).

Originally Posted by GeoffR

Could I ask those of you who upgrade your internal SD card, what type of card you used (brand/size/class) and whether it had any effect on the speed or stability of the reader?

I gather from some other sites that class 2 or 4 cards are often best for hosting the operating system (i.e. Kobo's internal card), while class 6 or class 10 cards are better for large data files (Kobo's external card perhaps?)

I also heard that not all types of card work well with Kobo readers, so it might be useful for those of us contemplating an upgrade to know which cards to avoid.

Speed is mainly an issue with the screen and CPU. The SD card won't be a bottleneck so won't really change anything unless possibly if you have huge books in which case a class 10 should go faster. Also booting up may go faster with a class 10 but I didn't really notice a huge difference.

By the way, Class 10 doesn't mean much. It should generally be faster than a lower class card but not in all cases. For example, a really good Class 6 can beat a really bad Class 10 in many areas.

As for stability, it mainly depends on the manufacturer from my experience but generally it doesn't matter.

Really, just avoid cheap, no-name brands or anything bought from Chinese eBay sites or anything like that. Genuine cards from SanDisk and Patriot at least should be fine. Especially SanDisk (they're the ones who manufacture the internal SD in the first place).

Oh and I'm not sure where the idea that a lower class card should be used for the system card came from. Can you give me a link and/or the reasoning they used? I can't think of any good reason to suggest this.

EDIT: Oh and I didn't mention. I'm using a 16GB Patriot card in mine.

[GeoffR]

Originally Posted by bobobo1618

Oh and I'm not sure where the idea that a lower class card should be used for the system card came from. Can you give me a link and/or the reasoning they used? I can't think of any good reason to suggest this.

The main idea seems to be that class 6 and 10 cards have been optimised for large sequential read/write operations at the expense of small random read/writes, but much operating system performance depends on small random writes (such as updating the KoboReader sqlite database).

This comparison for example suggests that class 4 scandisk and silicon power cards are up to 100x faster than patriot class 10 cards for some small random write operations:

http://www.tomshardware.com/reviews/...e,3011-12.html

[bobobo1618]

Originally Posted by GeoffR

The main idea seems to be that class 6 and 10 cards have been optimised for large sequential read/write operations at the expense of small random read/writes, but much operating system performance depends on small random writes (such as updating the KoboReader sqlite database).

This comparison for example suggests that class 4 scandisk and silicon power cards are up to 100x faster than patriot class 10 cards for some small random write operations:

http://www.tomshardware.com/reviews/...e,3011-12.html

Ahh, yes. Of course. I'm silly.

Then I'd recommend following your own reasoning and go with the benchmarks, looking for good random read/write speeds ^.^

As I said earlier, I haven't noticed any difference between the Class 10 Patriot card I have now and the Class 4 SanDisk card I had earlier though.

WOW though. Those Class 4 cards make a HUGE difference in the random write tests.

[GeoffR]

Originally Posted by bobobo1618

WOW though. Those Class 4 cards make a HUGE difference in the random write tests.

The problem of course is that the Kobo probably has to do large sequential reads too, such as when opening a book or loading a cover image. I don't know whether the performance gain in those operations from using a class 10 card would make up for the slower random writes.